Java json转换实体类(JavaBean)，实体类(JavaBean)转换json

JSON转换实体类

1. 使用Jackson库

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        ObjectMapper mapper = new ObjectMapper();
        try {
            User user = mapper.readValue(json, User.class);
            System.out.println(user.getName());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. 使用Gson库

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.6</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.google.gson.Gson;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        Gson gson = new Gson();
        User user = gson.fromJson(json, User.class);
        System.out.println(user.getName());
    }
}

3. 使用Fastjson库

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>2.0.15</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.alibaba.fastjson.JSON;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        User user = JSON.parseObject(json, User.class);
        System.out.println(user.getName());
    }
}

4.在线工具

此外，还有一些在线工具可以帮助你将JSON转换为Java实体类，例如：

• JSON中文网的在线JSON转JavaBean工具https://www.json.cn/json2java/

这些工具和库可以帮助开发者更方便地将JSON数据转换为Java对象，从而简化数据处理过程。

实体类转换JSON

1. 使用Jackson库

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.13.0</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        ObjectMapper mapper = new ObjectMapper();
        try {
            String json = mapper.writeValueAsString(user);
            System.out.println(json);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. 使用Gson库

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.6</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.google.gson.Gson;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        Gson gson = new Gson();
        String json = gson.toJson(user);
        System.out.println(json);
    }
}

3. 使用Fastjson库

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>2.0.15</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.alibaba.fastjson.JSON;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        String json = JSON.toJSONString(user);
        System.out.println(json);
    }
}

4.在线工具

此外，还有一些在线工具可以帮助你将Java实体类转换为JSON，例如：

• JSON中文网的在线JavaBean转JSON工具https://www.json.cn/json2java/

这些工具和库可以帮助开发者更方便地将Java对象转换为JSON字符串，从而简化数据传输和存储过程。